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Recently, various types of regular black hole model are reintroduced as thesolution of the Einstein equations coupled with nonlinear electrodynamics(NED). In NED, it is known that photons do not propagate along the nullgeodesics of the spacetime geometry, but of so-called effective geometry, whichsuggests the possibility of so-called ``faster/slower than light" photons. Westudy the relation between the causality of photons and the dominant energycondition (DEC) in some static and spherically symmetric black hole spacetimesin NED. We show that if photon trajectories with a nonzero angular momentum aretimelike in the spacetime geometry, DEC is always satisfied in static andspherically symmetric spacetimes in any NED that admits the Maxwell limit, andvice versa, at least, in the weak field limit. Thus, this implies that in suchNED, the violation of DEC admits the existence of faster than light photons.

Causality of Photon Propagation under Dominant Energy Condition in Non-linear Electrodynamics